U.S. Government says, exercise, exercise, exercise!

About two-thirds of Americans each year try to start regular exercise programs, according to a recent poll, but nothing like as many stay with it. The number of overweight and obese Americans is growing at an alarming rate.

Almost 40 percent of adults do no physical activity during leisure time according to data from the federal Centres for Disease Control and Prevention taken in 2002.

Now a panel of doctors and scientists are recommending at least 30 minutes of exercise each day and this after its 25 paged document which recommended 60 to 90 minutes each day, was scaled down to three pages, when released as part of the government's new dietary guidelines in January.

People who regularly work out at the gym say the majority of people will not consider that, and even the experts behind the government's recommendation say 30 minutes a day is enough for most.

Russell Pate, a panel member and professor of exercise science at the University of South Carolina school of public health says much needs to be clarified; if everyone met the 30-minute guideline, there would be fewer with weight problems.Pate said it was a mistake not to tie the half-hour recommendation to people's weight.

The guidelines are being used to update the government's food pyramid. This is what they say about exercise:

30 minutes of physical activity a day.

To prevent unhealthy weight gain, people should spend 60 minutes on physical activity each day.

Previously overweight people who have lost weight may need as much as 90 minutes of exercise.

In the guidelines, which advise people on healthy eating weight, is an issue throughout and they advise eating fewer calories, more fruits, vegetables and whole grains. People should also drink more lowfat milk, eat less fat and salt and exercise more. Exercise can be broken up into bouts of 10 to 15 minutes as long as it totals to at least 30. Do at least 30 minutes of moderate physical activity - the equivalent of walking briskly, at about 3.5 miles an hour. Other examples of moderate exercise are hiking, light gardening or yard work, dancing, golf, bicycling, a light workout of weight lifting. Stretching also counts.

The committee said more vigorous activity is even better, running or jogging at 5 miles an hour, walking at 4.5 miles an hour, bicycling at 10 miles an hour, swimming, aerobics, heavy yard work such as chopping wood, more vigorous weight lifting or playing basketball.